Jimi Diaz, an APS solar operations electrical engineer, adjusts the connection of a solar panel to a power output meter, at the APS STAR Center at the Ocotillo Power Plant in Tempe.

Jimi Diaz, an APS solar operations electrical engineer, explains the alignment of solar panels and its relation to power demands, at the APS STAR Center at the Ocotillo Power Plant in Tempe.

Jimi Diaz, an APS solar operations electrical engineer, compares electrical output readings on a south-facing panel and west-facing panel, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening.

Jimi Diaz, an APS solar operations electrical engineer, checks electrical output readings on a south-facing panel and west-facing panel, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Marc Romito, manager of APS' renewable energy, walks behind Diaz. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening. APS is proposing to install more solar panels that face west, which would increase the amount of power they generate later in the day.

Jimi Diaz, an APS solar operations electrical engineer, explains the alignment of solar panels and its relation to power demands, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening. APS is proposing to install more solar panels that face west, which would increase the amount of power they generate later in the day.

Jimi Diaz, an APS solar operations electrical engineer, shows peak solar output doesn't match peak demand, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening. APS is proposing to install more solar panels that face west, which would increase the amount of power they generate later in the day.

01/06

Jimi Diaz, an APS solar operations electrical engineer, adjusts the connection of a solar panel to a power output meter, at the APS STAR Center at the Ocotillo Power Plant in Tempe.

02/06

Jimi Diaz, an APS solar operations electrical engineer, explains the alignment of solar panels and its relation to power demands, at the APS STAR Center at the Ocotillo Power Plant in Tempe.

03/06

Jimi Diaz, an APS solar operations electrical engineer, compares electrical output readings on a south-facing panel and west-facing panel, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening.

04/06

Jimi Diaz, an APS solar operations electrical engineer, checks electrical output readings on a south-facing panel and west-facing panel, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Marc Romito, manager of APS' renewable energy, walks behind Diaz. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening. APS is proposing to install more solar panels that face west, which would increase the amount of power they generate later in the day.

05/06

Jimi Diaz, an APS solar operations electrical engineer, explains the alignment of solar panels and its relation to power demands, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening. APS is proposing to install more solar panels that face west, which would increase the amount of power they generate later in the day.

06/06

Jimi Diaz, an APS solar operations electrical engineer, shows peak solar output doesn't match peak demand, at the APS STAR Center at the Ocotillo Power Plant in Tempe, on Friday, September 26, 2014. Most solar panels produce maximum output mid-day, while the highest electricity demand in in early evening. APS is proposing to install more solar panels that face west, which would increase the amount of power they generate later in the day.